#R = 7/(4 − 6 sin(theta))# Convert the polar equation to rectangular form. ?

1 Answer
Mar 29, 2018

I shall begin by graphing the original polar equation #r = 7/(4 − 6 sin(theta))#

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Multiply both sides by #4-sin(theta)#

#4r - 6rsin(theta) = 7#

Substitute #r = sqrt(x^2+y^2)# and #rsin(theta) = y#:

4sqrt(x^2+y^2) -6y = 7

Add #6y# to both sides:

4sqrt(x^2+y^2) = 6y + 7

Square both sides:

#16(x^2+y^2) = (6y+7)^2#

Expand the squares:

#16x^2+16y^2 = 36y^2+84y+49#

This is the standard Cartesian form for conic section:

#16x^2-20y^2 -84y- 49 = 0#

Here is its graph:

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Please observe that the two graphs are identical.